Filament fastener



FIG. 1 is a top plan view of a filament fastener showing my new design;

FIG. 2 is an enlarged scale top plan view thereof, an intermediate section of the filament being broken away and omitted for ease of illustration;

FIG. 3 is a bottom plan view thereof;

FIG. 4 is a front elevational view thereof;

FIG. 5 is an enlarged scale fragmentary perspective view of the left end of FIG. 2;

FIG. 6 is an enlarged scale left end elevational view of FIG. 4; and

FIG. 7 is a right end elevational view thereof. 

The ornamental design for a filament fastener, substantially as shown and described. 